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  2. Redo log - Wikipedia

    en.wikipedia.org/wiki/Redo_log

    In the Oracle RDBMS environment, redo logs comprise files in a proprietary format which log a history of all changes made to the database. Each redo log file consists of redo records. A redo record, also called a redo entry, holds a group of change vectors, each of which describes or represents a change made to a single block in the database.

  3. Data deduplication - Wikipedia

    en.wikipedia.org/wiki/Data_deduplication

    The reasons for this are two-fold: First, data deduplication requires overhead to discover and remove the duplicate data. In primary storage systems, this overhead may impact performance. The second reason why deduplication is applied to secondary data, is that secondary data tends to have more duplicate data.

  4. Data orientation - Wikipedia

    en.wikipedia.org/wiki/Data_orientation

    Data orientation is the representation of tabular data in a linear memory model such as in-disk or in-memory. The two most common representations are column-oriented (columnar format) and row-oriented (row format). [1] [2] The choice of data orientation is a trade-off and an architectural decision in databases, query engines, and numerical ...

  5. Don't repeat yourself - Wikipedia

    en.wikipedia.org/wiki/Don't_repeat_yourself

    "Don't repeat yourself" (DRY), also known as "duplication is evil", is a principle of software development aimed at reducing repetition of information which is likely to change, replacing it with abstractions that are less likely to change, or using data normalization which avoids redundancy in the first place.

  6. Record linkage - Wikipedia

    en.wikipedia.org/wiki/Record_linkage

    Record linkage (also known as data matching, data linkage, entity resolution, and many other terms) is the task of finding records in a data set that refer to the same entity across different data sources (e.g., data files, books, websites, and databases).

  7. DUAL table - Wikipedia

    en.wikipedia.org/wiki/DUAL_table

    The idea was that you could do a JOIN to the DUAL table and create two rows in the result for every one row in your table. Then, by using GROUP BY, the resulting join could be summarized to show the amount of storage for the DATA extent and for the INDEX extent(s). The name, DUAL, seemed apt for the process of creating a pair of rows from just one.

  8. Surrogate key - Wikipedia

    en.wikipedia.org/wiki/Surrogate_key

    The unique index serves two purposes: (i) to enforce entity integrity, since primary key data must be unique across rows and (ii) to quickly search for rows when queried. Since surrogate keys replace a table's identifying attributes—the natural key —and since the identifying attributes are likely to be those queried, then the query ...

  9. Oracle Advertising - Wikipedia

    en.wikipedia.org/wiki/Oracle_Advertising

    Oracle Advertising, formerly Datalogix, is an American cloud-based consumer data collection, activation, and measurement platform for use by digital advertisers. Datalogix was a consumer data collection company based in Westminster, Colorado that provided offline consumer spending data to marketers that was acquired by Oracle in 2014.